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International
Crane Foundation
Foils Predators
With Electric
Fences
Cranes
rely on open
freshwater
wetlands for
survival during
most of their
lifecycle. The
loss and
degradation of
these kinds of
habitats are
among the most
pressing threats
to the survival
of these huge
birds. Another
threat, of
course, is the
ever-present
danger of
predators such
as raccoons and
mink.
The
International
Crane
Foundation,
founded in 1973,
operates a 25
acre compound
north of
Baraboo,
Wisconsin
devoted to
protecting this
endangered
species which
are “the largest
and oldest
flying birds in
the world,”
according to ICF
spokesman Dave
Chesky.
About 20 acres
are fenced and
netted to
protect the
birds. Chesky
says the site is
home for over
120 cranes
including every
species. “We’re
the only place
that has all of
them – whooping
cranes, sandhill
cranes, Siberian
cranes – all 15
species.”
Most of the
birds are part
of a protected,
captive flock;
permanent,
non-migratory
cranes held in
place by and
overhead netting
that keeps them
from flying
away. The
perimeter fence
that shields
them from
predators is an
ingenious
masterpiece of
engineering
created to keep
some wily
animals from
gaining access
to the rare
birds.
Chesky described
the protective
perimeter this
way: “To keep
burrowing
animals out,
we’ve got a
two-foot wide
wire mesh buried
two inches
underground in
front of the
fence. The
fence is eight
feet tall with
the first four
feet made of one
inch mesh chain
link fencing.
Over the years,
we’ve learned to
size it slightly
smaller than a
mink’s skull to
prevent them
from entering
the area.”
The top four
feet is a
Gallagher
supplied
electric fence
powered by B-260
chargers. “The
chargers have
proven very
reliable,” said
Chesky. “We
just had one
that was about
20 years old
rebuilt by the
factory and
reinstalled it.
It works
perfectly.”
Wires are set
just one inch
apart at the
bottom of this
powered section
and spaced wider
at the top. The
fence has ended
the foundation’s
losses to
predators. “We
haven’t lost a
bird since it
was installed,”
said Chesky.
According to
Erwin Quinn,
president of
Gallagher,
“An electric
fence is a
psychological
barrier that
keeps animals
where they
should be with
safety and
security.
Because the
fence is a
psychological
barrier, it
doesn’t require
great strength
to be effective.
However, it must
be well designed
in accordance
with the species
to be
controlled.”
The company,
based in North
Kansas City,
Missouri, is one
of the world’s
largest
manufacturers of
electric fences
designed to
contain cattle,
horses and other
farm animals as
well as prevent
wild animals and
predators from
gaining access
to areas where
they can do
economic damage. |